1. Field of the Invention
The present invention relates to switching control devices capable of controlling operation of switching elements in an electric power converter having a direct current voltage converter and an electric power converter which converts a direct current power output from the direct current voltage converter.
2. Description of the Related Art
Conventionally, there has been known a switching control device capable of controlling operation of switching elements in an electric power converter having a direct current voltage converter and a power converter. The power converter is capable of converting a direct current power output from the direct current voltage converter. The switching control device is capable of avoiding generation of a superimposed surge voltage caused when switching timings of the switching elements are overlapped with each other.
For example, a patent document 1 (Japanese patent laid open publication No. 2011-160570) discloses a switching control device capable of delaying a switching timing of switching elements in an inverter to a completion timing of a predetermined inverter shutdown period (switching inhibition period) when a switching timing of switching elements in a boost converter as the direct current voltage converter and a switching timing of switching elements in an inverter as the power converter are overlapped with each other.
However, the switching control device disclosed by the patent document 1 has possible deterioration of controllability of the inverter due to a large delay of the switching timing in the inverter and possible fluctuation of an output torque of the motor generator, i.e. a possible increasing of fluctuation of the motor generator when successive switching operations occur in the boost converter.
It is therefore desired to provide a switching control device capable of avoiding generation of a superimposed surge voltage in a direct current voltage converter and a power converter, and suppressing fluctuation in output of a load.